Processing Keyword Queries Under Access Limitations

  • Andrea Calì
  • Thomas W. Lynch
  • Davide Martinenghi
  • Riccardo Torlone
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9398)


The Deep Web is constituted by data accessible through web pages, but not readily indexable by search engines, as they are returned in dynamic pages. In this paper we propose a framework for accessing Deep Web sources, represented as relational tables with so-called access limitations, with keyword-based queries. We formalize the notion of optimal answer and investigate methods for query processing. We also outline the main ideas of our implementation of a prototype system for Deep Web keyword search.



Andrea Calì and Thomas Lynch acknowledge support by the EPSRC grant “Logic-based Integration and Querying of Unindexed Data” (EP/E010865/1).


  1. 1.
    Torlone, R.: Towards a new foundation for keyword search in relational databases. In: AMW (2014)Google Scholar
  2. 2.
    Hristidis, V., Papakonstantinou, Y.: DISCOVER: keyword search in relational databases. In: VLDB, pp. 670–681 (2002)Google Scholar
  3. 3.
    Calì, A., Martinenghi, D.: Querying data under access limitations. In: ICDE, pp. 50–59 (2008)Google Scholar
  4. 4.
    Li, C., Chang, E.Y.: Answering queries with useful bindings. ACM Trans. Database Syst. 26(3), 313–343 (2001)CrossRefzbMATHGoogle Scholar
  5. 5.
    Kimelfeld, B., Sagiv, Y.: Finding and approximating top-k answers in keyword proximity search. In: PODS, pp. 173–182 (2006)Google Scholar
  6. 6.
    Vardi, M.: The complexity of relational query languages. In: STOC, pp. 137–146 (1982)Google Scholar
  7. 7.
    Xu Yu, J., Qin, L., Chang, L.: Search in relational databases: a survey. IEEE Data Eng. Bull. 33(1), 67–78 (2010)Google Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Open Access This chapter is distributed under the terms of the Creative Commons Attribution Noncommercial License, which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.

Authors and Affiliations

  • Andrea Calì
    • 1
    • 4
  • Thomas W. Lynch
    • 1
    • 5
    • 6
  • Davide Martinenghi
    • 2
  • Riccardo Torlone
    • 3
  1. 1.University of LondonBirkbeckUK
  2. 2.Politecnico di MilanoMilanoItaly
  3. 3.Università Roma TreRomeItaly
  4. 4.Oxford-Man Institute of Quantitative FinanceUniversity of OxfordOxfordUK
  5. 5.Reasoning Technology LtdLondonUK
  6. 6.Birkbeck University of LondonLondonUK

Personalised recommendations